TL and ESR signals of mollusc shells—correlations and suitability for the detection of irradiated foods

• Published in: Radiation physics and chemistry (Oxford, England : 1993) Vol. 54; no. 4; pp. 413 - 423
• Main Authors: Ziegelmann, B, Bögl, K.W, Schreiber, G.A
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.04.1999; Elsevier
• Subjects: Biological and medical sciences; Fish and seafood industries; Food industries; Fundamental and applied biological sciences. Psychology; Edible mollusc; Microbiological testing; Electron spin resonance spectrometry; Interspecific comparison; Calcite; X ray diffraction; Dose activity relation; Aragonite; Irradiated product; Radiation dose; Ionizing radiation; Gamma irradiation; Storage stability; Detection limit; Calcium carbonate; Shell(anatomy); Paramagnetic properties; Manganese II Ions; Thermoluminescence
• ISSN: 0969-806X; 1879-0895
• DOI: 10.1016/S0969-806X(98)00272-2

Measurements are described which show the suitability of TL and ESR measurements of mollusc shells for the detection of irradiation treatment. Experiments on 18 samples of molluscs belonging to 10 different species were carried out. Significant TL signals of the irradiated samples were obtained from 3 of the 10 species investigated, while the others did not show a higher signal than the unirradiated ones. When looking at the X-ray diffraction spectra, it became obvious that all the radiation-sensitive samples contained calcite and in most cases, also aragonite, while the unsensitive samples contained only aragonite. The TL intensities of the sensitive samples did not correlate to the contents of calcite estimated by X-ray diffraction. Analyses of ESR spectra showed that there is a correlation between relative content of Mn 2+ ions and TL intensities of these samples. In contrast to TL, the ESR spectra of all samples revealed high radiation-specific signals being very stable and dose-dependent. Experiments were carried out to characterize signal stability under various commercially used storage conditions and dose response of both TL and ESR and to examine the emission bands of TL. In the case of mollusc shells, ESR seems to be the more sensitive and widely applicable method than TL for detection of irradiation.